The present invention pertains to a coated body (and method of making the same) wherein the coating scheme is applied by chemical vapor deposition (CVD), and especially coated cutting inserts that are useful in material removal applications such as, for example, machining, turning, and milling. More specifically, the present invention pertains to a coated body (and method of making the same), such as, for example, a coated cutting insert wherein the coating scheme includes a TiAl2O3 coating layer applied by CVD, and wherein the coated cutting insert exhibits acceptable properties including suitability in high performance cutting applications, high speed cutting applications, improved thermal resistance, and improved wear resistance.
Heretofore, coated bodies, such as, for example, coated cutting inserts, have been used in material removal applications. The coating layers typically comprise hard refractory materials that exhibit the properties of thermal resistance and/or wear resistance. One primary purpose of using a coating on a cutting insert has been to lengthen the useful life of the cutting insert. Exemplary such ones of these coating schemes are described in some of the following documents: article entitled “Titanium doped CVD alumina coatings”, Surface & Coatings Technology 203 (2008), pages 350-356 by Hochaer et al., article entitled “Doped CVD Al2O3 coatings for high performance cutting tools”, Surface & Coatings Technology 163-164 (2001), pages 181-188 by Kathrein et al., U.S. Pat. No. 4,180,400 to Smith et al., Japanese Published Patent Application No. 59-085860A to a PARTS OF CUTTING TOOL, U.S. Pat. No. 4,746,563 to Nakano, U.S. Pat. No. 6,660,371 to Westphal et al., and U.S. Pat. No. 7,326,461 to Sottke et al.
As is apparent from the above documents, many different coating schemes for a coated cutting insert have been used in the past. According to these documents, each one of these coating schemes provides certain advantages. Even though there have been coating schemes that are supposed to provide certain advantages, there has always remained a desire to continue to lengthen the useful life, as well as to improve the high performance cutting applications properties, high speed cutting applications properties, improved thermal resistance properties, and improved wear resistance properties of the coated cutting inserts. The desire to lengthen the useful life, as well as to improve the high performance cutting applications properties, high speed cutting applications properties, improved thermal resistance properties, and improved wear resistance properties is extant for coated cutting inserts.
Thus, it would be highly desirable to provide a coated cutting insert (and method of making the same, which is useful in material removal applications, with improved properties wherein the CVD coating comprises a coating scheme that includes a coating layer of TiAl2O3. Further, it would be highly desirable to provide a coated cutting insert (and method of making the same), which is useful in material removal applications, wherein the CVD coating comprises a coating scheme that includes a coating layer of TiAl2O3 and the cutting insert has a lengthened tool life, as well as exhibits improved performance characteristics. Still further, it would be highly desirable to provide a coated cutting insert (and method of making the same), which is useful in material removal applications, wherein the CVD coating comprises a coating scheme that includes a coating layer of TiAl2O3 and the cutting insert has a lengthened tool life, as well as exhibits acceptable properties including suitability in high performance cutting applications, high speed cutting applications, improved thermal resistance, and improved wear resistance.